KR100709878B1 - Polycarbonate/polyester alloy resin composition having excellent impact-resistance, flowability and articles using the same - Google Patents

Abstract

The present invention relates to a polycarbonate / polyester-based alloy resin composition having excellent impact resistance and fluidity by applying a core-shell graft impact modifier and a branched graft impact modifier to a polycarbonate resin and a polyester resin. The polycarbonate / polyester alloy resin composition of the present invention can be applied to the production of various molded articles such as portable mobile communication devices, precision electrical and electronic parts, and automotive precision parts that require excellent impact resistance and fluidity.

Polycarbonate / polyester alloy resin, core-shell graft impact modifier, branched graft impact modifier, impact resistance, flowability

Description

POLYCARBONATE / POLYESTER ALLOY RESIN COMPOSITION HAVING EXCELLENT IMPACT-RESISTANCE, FLOWABILITY AND ARTICLES USING THE SAME}

The present invention relates to a polycarbonate / polyester-based alloy resin composition, and more particularly, by applying a core-shell graft impact modifier and a branched graft impact modifier to a polycarbonate resin and a polyester resin. The present invention relates to a polycarbonate / polyester-based alloy resin composition having fluidity.

In general, polycarbonate / polyester-based alloy resins have been widely used as parts of automobiles and electronic products due to their chemical resistance and high impact strength. This is because when the polyester-based resin is applied to the polycarbonate resin by alloy, the excellent impact resistance of the polycarbonate is maintained, and the chemical resistance due to the polyester-based resin is improved, thereby showing excellent overall physical properties.

Meanwhile, in order to inject relatively large parts such as automobile bumpers using polycarbonate / polyester-based alloy resins, high fluidity is required, so it is generally used to set the temperature higher than the recommended injection temperature in actual injection work. to be. However, such a high working temperature has a problem of adversely affecting the overall physical properties of the resin by causing decomposition and transesterification of the relatively unstable polyester group.

Regarding the improvement of impact resistance and fluidity of polycarbonate / polyester based alloy resins, U.S. Patent No. 3,864,428 discloses polycarbonate resins and core-shell forms in which a vinyl monomer is grafted onto a butadiene-based core. It is disclosed to improve the chemical resistance and impact resistance at the same time by using a copolymer as an impact modifier, but this has a problem that does not bring the enhancement of fluidity. In addition, European Patent No. 239,157 proposes to improve the fluidity by using low viscosity polycarbonate and low viscosity poly (1,4-butylene terephthalate) as polyester resin, but in this case, impact strength is lowered. There was a problem.

Therefore, there is a demand for the development of a new polycarbonate / polyester-based alloy resin composition that can satisfy both high impact resistance and high fluidity while maintaining chemical resistance and fatigue resistance.

The present invention has been made to solve the problems of the prior art described above,

One object of the present invention is a polycarbonate / polyester based alloy having excellent impact resistance and fluidity by applying a core-shell graft impact modifier and a branched graft impact modifier to a polycarbonate resin and a polyester resin. It is to provide a Roy resin composition.

Another object of the present invention is to provide a molded article produced using the above resin composition.

One aspect of the present invention for solving the above technical problem is a core-shell graph, based on 100 parts by weight of 30 to 80 parts by weight of polycarbonate resin (A) and 20 to 70 parts by weight of polyester resin (B) Polycarbonate / polyester-based alloy resin composition having excellent impact resistance and fluidity, comprising 0.5 to 20 parts by weight of the impact modifier (C) and 0.1 to 10 parts by weight of the branched graft impact modifier (D). do.

Another aspect of the present invention relates to a molded article produced using the resin composition.

The resin composition of the present invention may further include an inorganic additive, a heat stabilizer, an antioxidant, a light stabilizer, a pigment or a dye and the like as necessary.

Hereinafter, the present invention will be described in more detail.

The present invention is characterized by having excellent impact resistance and fluidity by applying a core-shell graft impact modifier and a branched graft impact modifier to a polycarbonate resin and a polyester resin. The description regarding each component which comprises the resin composition of this invention is as follows.

(A) polycarbonate resin

The polycarbonate resin used in the present invention is not particularly limited, but examples thereof include linear polycarbonate, bracnched polycarbonate, polyester carbonate copolymer, silicone copolymer polycarbonate and the like.

The method of preparing the polycarbonate resin is well known to those skilled in the art, and is generally prepared by reacting dihydric phenol and phosgene in the presence of a molecular weight modifier and a catalyst, or dihydric phenol and di It can be prepared using an ester interchange reaction of a carbonate precursor such as phenylcarbonate.

The dihydric phenol used in the present invention is preferably bisphenol, and more preferably 2,2-bis (4-hydroxyphenyl) propane (ie bisphenol A). The bisphenol A may be partially or wholly replaced by another dihydric phenol, and other dihydric phenols other than the bisphenol A may be hydroquinone, 4,4′-dihydroxydiphenyl, bis (4-hydroxyphenyl). Methane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 2,2-bis (3,5-dimethyl-4-hydroxyphenyl) propane, bis (4-hydroxyphenyl) sulfide, bis ( 4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) ketone, bis (4-hydroxyphenyl) ether, and 2,2-bis (3,5- Halogenated bisphenols such as dibromo-4-hydroxyphenyl) propane and the like can be exemplified. In addition, the polycarbonate resin in the present invention may be a homopolymer or a copolymer using two or more dihydric phenols, or a mixture of such resins.

The linear polycarbonate used in the present invention is preferably a bisphenol A-based polycarbonate resin, and the branched polycarbonate reacts a polyfunctional aromatic compound such as trimellitic anhydride and trimellitic acid with dihydroxyphenol and a carbonate precursor. The polyester carbonate copolymer is preferably prepared by reacting a bifunctional carboxylic acid with a dihydric phenol and a carbonate precursor.

In the present invention, the polycarbonate resin is preferably used in the range of 30 to 80 parts by weight. When using less than 30 parts by weight, the polycarbonate phase has a discontinuity, the impact resistance is greatly reduced, when using more than 80 parts by weight may interfere with the dispersibility of the polyester-based resin may have a problem of lowering the chemical resistance and fatigue resistance.

(B) polyester resin

The polyester resin used in the present invention may be selected from the group consisting of polyalkylene terephthalate, polyphenylene terephthalate and copolymers thereof represented by the following formula (1).

 (Where m is an integer from 2 to 4 and n is an integer from 50 to 300)

The manufacturing method of the polyester-based resin may follow a commonly used method, an example of a specific manufacturing method as follows.

First, an acid component, a glycol component, and an additive such as a catalyst and various stabilizers are added to a stainless reaction vessel equipped with a stirrer, and the low molecular weight ester condensation by-products are removed out of the system while maintaining the temperature of the reaction tube at 200 to 230 ° C. Simultaneously with the ester reaction, the reaction is terminated when the conversion rate of the ester reaction is usually 95% or more of the theoretical effluent of the low molecular weight ester byproduct. When the ester reaction is terminated, the condensation polymerization of the polyester is induced by decreasing the pressure in the tube to 1 mmHg or less while raising the temperature in the tube to 250 to 280 ° C. The polycondensation proceeds in this manner to stop the reaction at a suitable stirring load, break the vacuum as nitrogen and discharge the reactant to obtain a polyester resin usable in the present invention.

Examples of the acid component that can be used in the preparation of the polyester used in the present invention include terephthalic acid or lower alkyl esterified products alone or in small amounts with isophthalic acid, orthophthalic acid and aliphatic dicarboxylic acid or lower alkyl esterified products thereof. It can be used in combination with the glycol component, mainly ethylene glycol, propylene glycol or butylene glycol alone or a mixture thereof, or other small amounts of 1,6-hexanediol, 1,4-cyclohexane dimethanol and the like As the catalyst, it is common to use an oxide of antimony or an organotitanium compound such as tetrabutyl titanate, tetraisopropyl titanate, or the like. In addition, an organic tin compound alone or a mixture thereof with an organic titanium compound Alkali metal or acetate It can also be used. When using an organotitanium compound, magnesium acetate or lithium acetate may be used as a cocatalyst.

In the present invention, the polyester resin is preferably used in an amount of 20 to 70 parts by weight, and if less than 20 parts by weight, a discontinuous phase structure is formed in the polycarbonate, thereby reducing fatigue strength and chemical resistance. In the case of using more than a portion, the polycarbonate forms a discontinuous phase and the impact resistance rapidly decreases.

(C) Core-shell graft impact modifier

The core-shell graft impact modifier is a graft copolymer of vinyl monolayer in the core structure of rubber to form a hard shell, and the core-shell impact modifier used in the present invention is a diene rubber, an acrylate rubber, or a silicone type. One or more selected from rubber monomers are polymerized to prepare a core of rubbery polymer, and then styrene, α-methylstyrene, halogen or alkyl substituted styrene, acrylonitrile, methacrylonitrile, C1-C8 methacrylic acid alkyl ester And at least one monomer selected from unsaturated compounds such as C1-C8 acrylic acid alkyl esters, maleic anhydride, and C1-C4 alkyl or phenyl nucleosubstituted maleimide is prepared by graft copolymerization into a rubbery polymer, wherein the entire graft is The rubber content of the copolymer is preferably 30 to 90 parts by weight.

As the diene rubber, butadiene rubber, acrylic rubber, ethylene / propylene rubber, styrene / butadiene rubber, acrylonitrile / butadiene rubber, isoprene rubber, ethylene-propylene-diene terpolymer (EPDM) and the like may be used.

Examples of the acrylate rubbers include acrylates such as methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, hexyl methacrylate and 2-ethylhexyl methacrylate. A monomer is used, and the curing agent used is ethylene glycol dimethacrylate, propylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate or 1,4-butylene glycol dimethacrylate, allyl methacrylate. Acrylate, triallyl cyanurate and the like can be used.

The silicone rubber may be prepared from cyclosiloxane, and specific examples thereof include hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, trimethyltriphenylcyclotrisiloxane, and tetramethyltetra. Phenylcyclotetrosiloxane, octaphenylcyclotetrasiloxane, etc. may be used, and examples of the curing agent used may include trimethoxymethylsilane, triethoxyphenylsilane, tetramethoxysilane, or tetraethoxysilane. .

C _{1 -} C ₈ methacrylic acid alkyl esters or C ₁ -C ₈ Acrylic acid alkyl esters are esters prepared from monohydryl alcohols having 1 to 8 carbon atoms as methacrylic acid or esters of acrylic acid, and specific examples are methacrylic acid methyl ester, methacrylic acid ethyl ester or methacrylic acid. A propyl ester is mentioned, Among these, a methacrylic acid methyl ester is the most preferable.

In the present invention, the content of the core-shell graft copolymer is preferably 0.5 parts by weight to 20 parts by weight, more preferably 3 to 15 parts by weight, based on 100 parts by weight of the total amount of the polycarbonate resin and the polyester resin. If the amount is less than 0.5 parts by weight, there is no effect of impact reinforcement. If the amount is more than 20 parts by weight, the mechanical strength such as tensile strength, flexural modulus, etc. is increased.

(D) Branched graft impact modifier

Branched graft impact modifier used in the present invention is a binary copolymer of ethylene propylene (EPM), EP (EPR), ethylene propylene diene propylene copolymer (EPDM), allyl methacrylate Butadiene-styrene (MBS), styrene-butadiene-styrene triblock copolymer (SBS triblock copolymer), maleic hydride-modified EPM (EPM-g-MA), maleic hydride-modified SBS (SBS-g-MA ), Maleic hydride modified EPDM-g-MA, all-acrylic core-shell rubber, ethylene ethyl acrylate (EEA), styrene-butadiene rubber (SBR), ethylene vinyl Alcohol (EVOH), a variety of thermoplastic elastomers (thermoplastics elastomers) and plastomers (plastomer) may be selected from among those, preferably EPM, EPDM, EPAL, maleic hydride modified EP, maleic hydride De-modified EPDM and maleic hydride-modified PI.

In addition, carboxylic acid or maleic hydride may be further added to improve performance.

The content of the branched graft impact modifier used in the present invention is 0.1 to 10 parts by weight, preferably 0.3 to 5 parts by weight based on 100 parts by weight of the total of the polycarbonate resin and the polyester resin. When the branched graft impact modifier is 0.1 parts by weight or less, the impact resistance and fluidity are hardly improved, and when the branched graft impact modifier is 10 parts by weight or more, the mechanical properties such as flexural strength are greatly decreased.

The polycarbonate / polyester-based resin composition of the present invention may be used depending on the use by adding other additives, and specifically, when adding inorganic fillers such as glass fiber, carbon fiber, talc, silica, mica, alumina, Physical properties such as strength and heat deflection temperature can be improved. In addition, the resin composition of the present invention may be prepared by further including other ultraviolet absorbers, heat stabilizers, antioxidants, flame retardants, lubricants, dyes and / or pigments and the like.

In addition, since the polycarbonate / polyester alloy resin composition of the present invention has excellent impact resistance and fluidity, the polycarbonate / polyester alloy resin composition is required for the production of various molded articles such as portable mobile communication devices, precision electric and electronic parts, and automobile precision parts, which are required for such characteristics. Can be applied.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, this is for the purpose of explanation and is not intended to limit the claims of the present invention.

EXAMPLE

Polycarbonate resin (A), high viscosity polyester resin (B), core-shell graft impact modifier (C) and branched graft impact modifier used in Examples 1 to 4 and Comparative Examples 1 to 5 below ( The specification of D) is as follows.

(A) polycarbonate resin

PANLITE L-1250WP from TEIJIN, Japan was used as a bisphenol-A type linear polycarbonate having a weight average molecular weight of 25,000 g / mol.

(B) polyester resin

The polyester-based resin used a polybutylene terephthalate TRIBIT 1700 of Samyang, which has a specific gravity of 1.31 g / cm 3, a melting point of 226 ° C., and an intrinsic viscosity of 1.10.

(C) Core-shell graft impact modifier

As a core-shell graft impact modifier, C-223A from Japan MRC, a core-shell graft copolymer in which a methacrylic acid methyl ester monomer is grafted to butadiene rubber having a weight average particle diameter of about 0.3 μm, is used as an impact modifier. It was.

(D) Branched graft impact modifier

As the branch graft impact modifier, EXXELOR VA1803 from Exxon, an EPR (Ethylene-Propylene Rubber) grafted with maleic anhydride (maleic anhydride), was used.

The composition of each component used in Examples 1 to 4 and Comparative Examples 1 to 5 was mixed as shown in Table 1, and each component was mixed and prepared into pellets using a twin screw extruder having a diameter of Φ = 45 mm. The prepared pellets were dried at 110 ° C. for at least 3 hours, and then injected into a 10 oz injection machine under a molding temperature of 250 to 300 ° C. and a mold temperature of 30 to 60 ° C. to prepare a physical specimen.

[Property evaluation method]

(1) liquidity

Melt Flow Rate was measured according to ASTM D1238 prior to specimen preparation. The measurement temperature is 250 ℃ and the mass of the resin flowing out for 10 minutes using a weight of 10kg is shown in Table 1 below.

In order to measure the length of the flow field indicated by the resin under actual injection conditions, the length of the practical flow field is measured by maintaining the specimen mold having a thickness of 1mm at 60 ° C and injecting with 95% force in a 10oz injection machine. Was measured. The length of the practical flow field is shown in Table 1 below in Comparative Example 2 based on 100%.

(2) impact resistance

The prepared specimens were measured in a notched Izod impact strength (1/4 ") according to ASTM D256 and are shown in Table 1 below.

Falling impact test was used to drop the specimen by changing the height using a weight of 2kg in accordance with ASTM D3029 to observe the failure pattern, and repeatedly evaluated for 20 specimens to measure the failure rate. The failure pattern was determined by dividing the specimen into ductile fracture, in which cracks did not occur and only entering concave by impact, and brittle fracture, in which cracks occurred. It is shown in Table 1 below as a ratio.

Dropping impact test was carried out before and after coating treatment, coating treatment was evaluated by immersion in a solvent for 20 seconds using Thinner 276 of Daihan Bee Chemical, and then dried for 5 minutes at 70 ℃.

As shown in Table 1 above, when the core-shell graft impact modifier and the branched graft impact modifier are alloyed together with the polycarbonate / polyester-based resin (Examples 1 to 4), high impact resistance and You can see that high fluidity is implemented together.

 On the other hand, as shown in the results of Comparative Examples 1 to 5, when using one of the core-shell graft impact modifier or branched graft impact modifier alone, the polycarbonate / polyester resin in the same content ratio Although it does not show a big difference in fluidity, it can be seen that impact resistance and fatigue strength are inferior.

The present invention provides a polycarbonate / polyester-based alloy resin composition having excellent impact resistance and fluidity by applying a core-shell graft impact modifier and a branched graft impact modifier to a polycarbonate resin and a polyester resin. The polycarbonate / polyester alloy resin composition of the present invention may be applied to the production of various molded articles such as portable mobile communication devices, precision electric and electronic parts, and automobile precision parts, which are required to have excellent impact resistance and fluidity. .

Claims (5)

0.5 to 20 parts by weight of core-shell graft impact modifier (C) and branched graft based on 100 parts by weight of 30 to 80 parts by weight of polycarbonate resin (A) and 20 to 70 parts by weight of polyester resin (B) A polycarbonate / polyester-based alloy resin composition comprising 0.1 to 10 parts by weight of an impact impact modifier (D), The core-shell graft impact modifier (C) is a styrene, α-methylstyrene, halogen in the core of the rubbery polymer prepared by polymerizing at least one selected from the group consisting of diene rubber, acrylate rubber and silicone rubber monomer Or in an unsaturated compound consisting of alkyl substituted styrene, acrylonitrile, methacrylonitrile, C1-C8 methacrylic acid alkyl esters, C1-C8 acrylic acid alkyl esters, maleic anhydride and C1-C4 alkyl or phenyl nucleosubstituted maleimides Prepared by graft copolymerization of one or more selected monomers, The branched graft impact modifier (D) is EPM, EPR, EPDM, allyl methacrylate-butadiene-styrene (MBS), styrene-butadiene-styrene triblock copolymer (SBS triblock copolymer), maleic hydride-modified EPM (EPM-g-MA), maleic hydride-modified SBS (SBS-g-MA), maleic hydride-modified EPDM-EP-G-MA, 1 selected from all-acrylic core-shell rubber, ethylene ethyl acrylate (EEA), styrene butadiene rubber (SBR), ethylene vinyl alcohol (EVOH), thermoplastic elastomer and plastomer Polycarbonate / polyester-based alloy resin composition having excellent impact resistance and fluidity, characterized in that more than. The method of claim 1, wherein the content of the core-shell graft impact modifier (C) is 3 to 15 parts by weight, and the content of the branched graft impact modifier (D) is 0.5 to 5 parts by weight. Polycarbonate / polyester-based alloy resin composition having impact resistance and fluidity. According to claim 1, wherein the polyester resin is polyalkylene terephthalate, polyphenylene terephthalate represented by the following formula (1) or a poly having excellent impact resistance and fluidity, characterized in that selected from the group consisting of copolymers thereof Carbonate / polyester based alloy resin composition. [Formula 1]

  (Where m is an integer from 2 to 4 and n is an integer from 50 to 300) The method of claim 1, wherein the resin composition further comprises at least one member selected from the group consisting of inorganic additives, heat stabilizers, antioxidants, light stabilizers, pigments and dyes. Polycarbonate / polyester alloy resin composition having excellent impact resistance and fluidity. The molded article manufactured using the resin composition of any one of Claims 1-3.